1 // Protocol Buffers for Go with Gadgets 2 // 3 // Copyright (c) 2018, The GoGo Authors. All rights reserved. 4 // http://github.com/gogo/protobuf 5 // 6 // Redistribution and use in source and binary forms, with or without 7 // modification, are permitted provided that the following conditions are 8 // met: 9 // 10 // * Redistributions of source code must retain the above copyright 11 // notice, this list of conditions and the following disclaimer. 12 // * Redistributions in binary form must reproduce the above 13 // copyright notice, this list of conditions and the following disclaimer 14 // in the documentation and/or other materials provided with the 15 // distribution. 16 // 17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 20 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 21 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 23 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 29 // +build purego appengine js 30 31 // This file contains an implementation of proto field accesses using package reflect. 32 // It is slower than the code in pointer_unsafe.go but it avoids package unsafe and can 33 // be used on App Engine. 34 35 package proto 36 37 import ( 38 "reflect" 39 ) 40 41 // TODO: untested, so probably incorrect. 42 43 func (p pointer) getRef() pointer { 44 return pointer{v: p.v.Addr()} 45 } 46 47 func (p pointer) appendRef(v pointer, typ reflect.Type) { 48 slice := p.getSlice(typ) 49 elem := v.asPointerTo(typ).Elem() 50 newSlice := reflect.Append(slice, elem) 51 slice.Set(newSlice) 52 } 53 54 func (p pointer) getSlice(typ reflect.Type) reflect.Value { 55 sliceTyp := reflect.SliceOf(typ) 56 slice := p.asPointerTo(sliceTyp) 57 slice = slice.Elem() 58 return slice 59 } 60